Control device for engine fuel systems



2 Sheets-Sheet 1 Original Filed April 1, 1946 all.

2% 0L Tss V N I E E WA LJ UE 62 114. rla/ ATTORNEY Aug. 28, 1951 L. E.ENDSLEY ETAL CONTROL DEVICE FOR ENGINE FUEL SYSTEMS 2 Sheets-Sheet 2Original Filed April 1, 1946 ATTORNEY Patented Aug. 28, 1951 Louis E.Endsley, Pittsburgh,.Ba., and James E. V Justus, Beloit; Wis., assignorsto Fairbanks, Morse & 00., Chicago, 111;, a corporation of IllinoisOriginal application April 1', 1946, Serial No.- 658,674; Dividedandthis application May 16, 19 49, SerialNo.93,452

1 Claim; 1

This invention relates to improvements inthe fueling. of internalcombustion engines, andhas particular reference to improved controlmecha nism for the fuel delivery apparatus of engines such. as dieselengines of the opposedpiston type. The present application is a divisionof appl'ica tion-Serial No. 658,674, filed April 1, 194$,and entitledEngine Fuel Gontrol Means, said app1ication now being Patent No.2,496,458.

It is well known in diesel enginepractice and particularlyin theinstance of opposed piston diesels,. to employ for the purpose ofimproved combustion. efficiency, two or morefuel injectors in eachcylinder arranged as in diametrical or othersuitably spaced relation toafford a uniform and more effective fuel distribution in the cylindercombustion space. However, in connec" tion. with. fuel systems utilizingairless or solid fuelinjectors of well-known. or prevailingconstruction, it'has: been found in practice that during engineoperation under no load, idlin -speed andsometimes under light loadconditions with enginespeedonly slightly above idling, fuel-deliverythrough the injectorstends to be in excess ofthat quantity. necessarymerely to maintain enginer idling or low speed operation. Wheretheengine is. employed as a prime moverior: railway locomotives, as switchand transfer locomotives in particular, frequent and many timesarelative13') long periods ofengine: operation at idling or low'speed, areencountered in normal locomotive use, so that the problem of excess fuelconsumption or fuel wastage during idling in particular,

is of major importancein diesel locomotive practies. In fact, if notprevented, the excess fuel not consumed in the normal combustion processat idling or low speeds, ultimately will leak past the pistons into theengine crankcase andthere mix with thelubrication oil. with consequentdi lutionof the latter to a more or less serious: degree; Intime, theaccumulation of fuel-oil in the crankcase may reach proportionsdangerousfor obvious reasons, to further engine operation. Accordingly, it is aprincipalpurpose of the present invention to provide in operativeassociation with the fueling apparatus of a dieselengine: of opposedpiston type in particular. employing two or more fuel injectors in eachcylinder thereof, control means of a novel and effective character, for:regulating engine fueling in amanner such as-will avoid the conditionabove'expressed.

Stated more particularly, the'present improvements afford an enginegovernor-responsive controlmechanism forl regulating fuelwpump deliveryto the injectors of the cylinders such thatdurcient merely to continueidling or low speed operation. Under load operationof the engine, thecontrol mechanism functions in responseto governoraction, to determinepump fueldelivery to all of the injectors, and to effect at least atfull load, an equal fuel quantity injection by the injectors in-eachcylinder.

Another object of the present invention" is to embody in a fuel deliverycontrol mechanism for the purpose indicated, means for actuating thecontrol in the event of failure of'normal oil pres sure in the enginelubricating system, to cause an immediate reduction in fuel pumpdelivery such as will stop further operation of. the engine;

The foregoing. and other objects will appear readily from thefollowingdescription of'a presently. preferred embodiment of theinvention" as exemplified in the accompanying drawing, where in:

Fig. l isa fragmentary horizontalsectioiiof'an engine embodying thepresent im rovements; the view showing one cylinder, injectors and fuelpumps in diagrammatic elevation;

Fig. 2 is a view similar to that of Fig, 1,-but illustrating the controlmechanism in the p'osi tion of no-fuel delivery adjustment of the fuel.P QP L Fig. 3 is. a detail. view of a pa'rt'o'f the governoroperatedmechanism, as taken along th'e'line' 3-3 in-Iii'g. 1', and VFig. 4 illustrates graphically, fuel quantity'de livery by the oppositepumps'correspondifig to rack positions, and indicates the relativepositions of'the racks throughout engine operation.

In. the drawing there are shown insomewhat diagrammatic manner;o'nlysuch parts'ofa diesel engine of an opposed piston ty e," which'areconsideredessential or desirable toa full understand .ing of the presentinvention. The'engineframe suitable position on opposite sides of thecylinder H' are fuel pumps [Band l9, which mayi'bealike and-of any wellknown construction. By' resent preference, the pumps areofreciprocat'ing plungier type, each driven by theengineasthroiugh acam-shaft (not shown).andregulatable as to fuel quantity delivery byangular adjustment of. it's plunger through a rack controlelementihdicat'd aaeaose I at Zll. Fuel delivery is eifected from pump[8 through a conduit 22 to an air-less injection valve 23 in thecylinder I I, for injection to the cylinder combustion space. In likemanner, the pump [9 delivers through a conduit 25 to an injection valve24 located in the cylinder preferably dia- V metrically opposite theinjection valve 23.

While but one cylinder II is here shown, in engines of more than onecylinder, each cylinder will have associated therewith a like pair offuel pumps and cylinder injectors, arranged as described for thecylinder shown. The group or bank of pumps on one longitudinal side ofthe engine, as on the right hand side as viewed in Fig. 1, may beregulated simultaneously as to fuel quantity output, from the enginegovernor indicated diagrammatically at 26, through control mechanismforming the subject of this invention and presently to be described. Therack element 2i] of each pump in the bank, is suitably adjustablyconnected to a rod 21 by an operating link 28, as indicated for the pump58 shown, from which it will appear that upon longitudinal displacementmovements of rod 21, the rack of each pump will be actuated to adjustthe pump output. The pumps in the left hand bank similarly havertheirrack elements 20 adjustably connected to a common control rod 3!], thislatter being under governor control as will appear presently.

With reference now to the control mechanism between the governor 2B andthe pump rack actuating rods 21 and 30, an operating lever or rockingbeam 31 is arranged horizontally along the engine frame member and ispivotally supported by a pivot assembly 32 including a bracket 34secured to the frame as by bolts 35. The lever is pivoted off-center toa predetermined extent for a purpose to appear, such that the portion 36between the point of pivotal support and the lever end 38 adjacent theend 39 of rod 21, is of greater length than the lever portion 40 betweenthe pivot and lever end 42 adjacent the end 43 of rod 38. Operativelyconnecting the lever end 42 and the end 43 of rod 30, l

is a link element 44 suitably pivotally secured to the rod and lever asshown. At the opposite lever end 38, the lever connection to the rod 21is made by means permitting a limited pivotal movement or over-travel ofthe lever without corresponding movement of the rod 21, as for a purposeto appear. The means referred to comprises by present preference, amember 46 pinned or otherwise suitably pivotally connected at one end41, to the end 39 of rod 2'1, and pivotally carried on the lever 31 by alink 48, the link being pivoted to the lever at a point inwardlyadjacent the lever end 38, and to the member 46 at a point inwardlyadjacent the end 56 of the latter. Carried by the end 50 of member 46 isan adjustable distance piece, shown as a cap screw 5| arranged forabutment with the lever 31. A suitable compression spring 52 having itsends seated in recesses or pockets, 54 and 55 formed respectively, inthe lever 3| and member 46, serves to retain the parts in normaloperative relation, as with the cap screw in abutment with the lever toafford a substantially rigid connection between the lever and rod 21throughout normal fuel regulating operation of the mechanism. However,in the lever actuation of rod 21 in the direction as indicated by thearrow 56, to reduce the fuel output of the pump to zero fuel delivery(Fig. 2), the connection as described will function to permitpositioning of the pump racks at zero fuel" positions. Thereafter uponfurther lever movement in the same direction for returning the oppositebank of pumps to zero fuel condition as will be referred to hereafter,the rod 21 at such time being held against further movement by abutmentof the pump racks with suitable stops (not shown), the spring 52 willyield, compressing as the end 38 of the lever 3i approaches the end 39of rod 21, while the member 46 pivots relative to rod 2'1, thus allowingthe desired overtravel of the lever 3i as to the position shown in IFig. 2.

- a projection 60 on the lever.

Governor connection to lever 3i preferably is made at the lever end '32,and comprises a yoke member 6! pinned to the lever at 62 and adjustablythreaded lengthwise into one end of a bar 64. The opposite end 65 of bar64 is freely projected through an aperture Eli transversely through thecentral part of a pivot pin 68, the latter being supported at its endsin spaced arms 69 forming a lever the hub portion 10 of Which (Fig. 3)is suitably secured or keyed upon one end of a shaft 15. A nut andwasher 13 on the free end of bar 64 when in abutment with pin 68,determines a positive actuating connection serving in one direction ofrotation of shaft 12, to produce pivotal displacement of the lever 3|.Pivotal movement of the lever in the opposite direction by shaftrotation opposite to that mentioned, is here effected, however, througha yieldable element comprising a compression spring [4 bearing between acap flange 16 on the bar 54 and a flanged washer H, the latter abuttingthe pin 68.

Shaft 15 is suitably rotably journalled by bearings 78 in the oppositeframe sides l2 and i4, and projects at 8!] for connection by a lever 8|,to the governor 28. Thus the lever system as now described, is underdirect control of the governor, for determining fuel delivery regulationoithe several fuel pumps in a manner now to be fully pointed out.

Before proceeding with the operation, it is to be noted that the rackelement 29 of each pump is provided with graduations arrangedlongitudinally over an exposed surface thereof and numbered from zero toseven (Fig. 1), while a pointer 84 fixed to the pump frame is associatedwith the graduations as shown. The pump assembly is adjusted such thatwhen the rack 20 is positioned to register the zero graduation with thepointer, the pump plunger will be thereby conditioned for no-fueldelivery to the injector, and further such that for example when therack is actuated to register graduation No. 3 with the pointer 84, thepump plunger thereby rotated to an extent corresponding to the rackdisplacement from zero to theNo. 3 graduation, will be conditioned forfuel delivery through the associated injector in quantity sufficientmerely to maintain engin operation at no-load, or at most, under aminimum load, low speed condition. Continued rack displacement'such asto register graduation No. 7 for example, with the pointer 84, therebyconditions the pump for fullload fuel delivery.

Turning now to the operation of the system, when the engine is not inoperation, the mechtsetse anism is positioned (Fig. 2) .asdetermined bythe inactive position of the governor 26, to dispose the control rod 39such as to locate the racks 23 of the left hand bank of fuel pumps, toregister the zero graduation of each with the associated pointer 84.SimiIarIy the racks Zoof the right hand bank of fuel pumps will bepositioned through rod 2'1, to register the zero graduation of each withthe associated pointer 84, the yieldable connection between the rod 27and the pivot bar or lever 3|, as constituted by the elements 46, 48 andspring52, being at this tim in what may be called a collapsed conditionsuch that with the lever end 38'relative1-yclosely adjacent the end, 39of-rod 21, the member 46 will be piretally displaced relative to-lever31 to a position wherein the stopelement 5| isout of engagement with thelever 31, as appears in Fig. 2. Now upon starting ofthe'engineand-adjustment of the governorzfi in a well known manner, to determine forexample, normal. no-load idling of the engine, the lever 3| will bepivotally actuated by the governor through the shaft 15 and thedescribed operating connection between the shaft and lever 31, todisplace-the control rod as sufficiently to cause actuation ,of the pumpracks 2t in the left hand pump bank, to register graduations No. 3 withthe fixedpointers. Pivoting of the lever 3] to this extent however, doesnot effect movement of rod 21' and the connected racks of the right handbank of fuel pumps, from the initial no-fuel delivery positionsofjth'ese elements, because as the end '38 of the lever moves away fromthe end 39 of the rod 21, the member 46 pivots about its connection torod '2'! until the stop element 5| engages the lever 3|, the latterobtaining (according to adjustment of the stop 5!) when the lever 3| isin the position to determine the aforementioned idling fuel delivery bythe left hand bank of pumps. During this phase of lever displacement,the spring 52 is expanding from its initial compressed condition, thespring reacting on the rod 21 through member 46 t prevent roddisplacement as the lever pivots, until the stop 5| contacts the lever.Thereafter, when the lever is pivoted beyond the idlin position as todetermine load operation of the engine, the described connection betweenthe lever and rod 21 affords positive displacement of rod 21 by thelever.

Now as the governor 26 is further regulated as for full load, full speedoperation of the engine for example, the lever 31 in response to governor actuation thereof, is pivoted in the direction to displace rod 30 toan extent such as to register the No. '7 graduation of each pump rack inthe left hand pump bank, with the associated pointer 34 (Fig. 1). Inthis instance, rod 30 is moved from the idling position wherein the No.3 graduation of each pump rack 20 is in register with its pointer. Asthis takes place, the lever also actuates the rod 21 in the direction tcause fuel delivery operation of the right hand bank of pumps. Since theportion 36 of lever 3| which is connected to rod 21, is the longer armof the lever, the resulting displacement of rod 21 will be greater thanthat of rod 30. In the present example, the relative lengths of thelever arms 36 and G0 is predetermined, as by proper location of thoff-center pivot 32 along the lever 3|, so that the rate of rack advancein the right hand bank of pumps, occurring between idling and ful speedoperation of the engine, is greater than that in the left hand bank ofpumps to an extent such that in the full load, full speed operation,both; banks ofpumps will be conditioned for equal fuel delivery to theinjectors. The No. '7 graduation of the rack element 28 of each pump ineach bank then will be in registry with its pointer 84. Consequently,under full load the fuel injection at each cylinder will be equallydivided between the two injectors therein. The foregoing is illustratedby Fig. 4, wherein the fuel quantity delivery by pump It varies withrack position substantially in accordance with the graph line Eldwhilthe graph line 86 indicates the same with respect to the pump it, butshows the greater rate of change of rack position of the latter pump inrespect to that of pump [9. From the graph, it appears that at engineidling, therack of pump I9 is at position 3, while the rack of pump [8is at zero setting. Thus fuel delivery to the cylinder obtains onlythrough the pump l9 and connected injector 24, and in quantitySllffiClETtLt merely to maintain engine idling. Beyond idling as underload operation of the engine, both pumps are in operation with relativefuel quantity delivery in accordance with the graph lines, up to fullload fuel delivery when th pumps deliver equal quantities of fuel,

It will be appreciated now that the present im provements afford agovernor responsive fuel control mechanism which is operative todetermine fuel delivery through only one injector in each cylinder atengine idling or low speed operation. The arrangement thus enables themost efiicient operation of the fueling means at idling for example,precluding the admission of more fuel than is necessary merely tomaintain the engine in operation under idling condition, therebyavoiding fuel wastage and crankcase lubricating oil dilution by fueloil, as would otherwise occur. Above idling, the mechanism determines inaccordance with governor setting, fuel delivery through all of thecylinder injectors, and effects at least at full load operation of theengine, equal quantity fuel injection at the injectors in each cylinder.

In the present embodiment of the invention, there is provided a safetydevice effective to cause a reduction in or stoppage of fuel delivery bythe pumps in the event of abnormally low oil pressure or pressurefailure in the engine lubricating system. As presently preferred andshown somewhat diagrammatically, the device indicated generally at 90and effective through the lever 3|, comprises a cylinder 9| suitablymounted on the engine frame member I2, adjacent the end 38 of lever 31,and a piston member 92 operable therein. The cylinder head or cap 94 iscentrally apertured at 95 to accommodate a shaft-like element 96projecting therethrough, the element 96 being carried by the piston 92and serving as a piston guide as well as the lever contact element ofthe device. A cap screw or the like 98, adjustably carried on the lever3 l, is positioned for engagement by the exposed endltil of element 96upon piston actuation as will be presently described. .A shaft-likeextension I02 from the opposite side of piston 92, is extended throughthe end portion I03 of the cylinder ill and cooperates with element 96to constrain the piston 92 to a straightline displacement in thecylinder. Extension I02 also affords a shoulder I04 which in engagementwith the cylinder end I83, determines the inactive position of thepiston. The pistonis biased in the direction to engage the element 96with the lever cap screw 98, by a suitable compression spring I06arranged as shown, but normally is as to actuate the racks of theseveral fuel pumps in the direction to cause fuel-delivery reduction orcessation at the pumps. The engine thus will stop, and since the safetydevice will hold the lever against fuel-increasing displacement untilthe piston 92 is retracted by normal lube oil pressure, the enginecannot be operated again until the cause of lube oil pressure failure isascertained and corrected. It is to be noted here that the engineshutdown operation of the device 90 as effected through the lever 31, isindependent of the governor control of lever 3|, this being facilitatedby the yieldable connection between the governor actuated shaft 12 andthe lever 3|, as afforded by the spring 14.

Having now shown and described the invention as to a presently preferredembodiment thereof, what We desire to claim by Letters Patent is:

In combination with an internal combustion engine providing a cylinder,at least two fuel admission valves for said cylinder, a fuel supply pumpindividual to each of said valves and including a control elementoperable to determine 8: the fuel output of each pump, a pressurelubrieating system, a pivotally supported control lever providing ashort arm and a long arm, means connecting said short arm to the controlelement of one pump, means including a lost-motion device connecting thelong arm to the control element of the other pump, governor meanssupported on said engine, a linkage connected between the outer free endof said short arm and said governor, a spring in said linkagetransmitting the movement of said governor to said short arm to pivotsaid control lever in one direction for increasing fuel delivery to saidengine, and an emergency shut down means responsive to pressure failurein said lubricating system and mounted on said engine directly below theouter free end of said long arm and movable thereagainst' to pivot saidcontrol lever in an opposite direction against the resistance of saidspring.

LOUIS E. ENDSLEY. JAMES E. JUSTUS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,170,200 VerPlanck Feb. 1, 19161,473,303 Lightford Nov. 6, 1923 2,010,420 Simmen Aug. 6, 1935 2,010,960Pogue Aug. 13, 1935 2,197,743 Crafts et a1 Apr. 16, 1940 2,225,234Schettler Dec. 17, 1940 2,496,458 Endsley et a1 Feb. 7, 1950

